Methods for removing calculus from an access sheath

ABSTRACT

A method involves introducing a raking part into a lumen in an ureteral access sheath in which is located calculus, wherein the raking part is introduced into the ureteral access sheath while at least a part of the ureteral access sheath is located in a living body. The raking part is moved in the ureteral access sheath toward the calculus and is positioned beyond the calculus. The lumen in the ureteral access sheath is at least partially occluded by way of the raking part. After at least partially occluding the lumen in the ureteral access sheath by way of the raking part, the raking part is moved along the lumen in the ureteral access sheath in a direction opposite the first direction so that the raking part rakes out the calculus.

CROSS-REFERENCE TO OTHER APPLICATIONS

This application discloses subject matter related to subject matterdescribed in U.S. application Ser. No. 14/222,021, U.S. application Ser.No. 14/221,954 and U.S. application Ser. No. 14/221,858, the entirecontent of each of which is incorporated herein by reference.

TECHNICAL FIELD

The present invention generally pertains to methods and systems forretrieving/removing a mass from a human body. More specifically, theinvention involves methods and systems for retrieving/removing stone(s)(e.g., calculus or calculi) from a portion of a human body such as therenal pelvis or the ureter.

BACKGROUND DISCUSSION

The term urinary calculus (calculi) (e.g., kidney stone(s) and ureteralstone(s)) refers to mass(es) or stone(s), typically solid particle(s),that form in the human body and is located in the kidney and/or theureter. They can exhibit a variety of chemical compositions includingcalcium oxalate, calcium phosphate, uric acid, cystine, and struvite.

Stone disease (e.g., kidney stones and ureteral stones) is a relativelycommon urological disorder. The presence of calculus in the body canmanifest itself in a variety of ways and can produce a number of medicalailments. For example, the presence of calculus in the renal pelvisand/or the renal calix (i.e., the lumen of the kidney) can cause bloodin the urine, urinary obstruction, infection, and various degrees ofpain ranging from vague frank pain to much more severe pain not capableof being relieved through general pain medication. The presence ofstones or calculi in the ureter can result in relatively severe side andback pain, pain below the ribs, and pain that sometimes spreads to thelower abdomen and groin, as well as pain during urination and hematuria.

Fortunately, many calculi or stones pass out of the body withoutrequiring any specific medical intervention. In those situations wherethe calculus does not naturally pass out of the body, a medicalprocedure may be required. Known medical procedures typically fall intothree categories.

In the past, three main treatments have been used to address calculus orkidney stones. These include shock wave lithotripsy (ESWL),transurethral lithotripsy or ureteroscopy (URS), and percutaneousnephrouretero lithotripsy (PCNL) which is sometimes also referred to aspercutaneous nephrolithotomy (PCN).

Shock wave lithotripsy is performed as an extracorporeal treatment. Thistreatment utilizes a machine called a lithotripter that operates bydirecting ultrasonic or shock waves from outside the body, through theskin and tissue, and at the calculi or stones. Repeated shock wavesapply stress to the stones, eventually breaking the individual stonesinto smaller pieces which can more easily pass through the urinary tractin urine. One benefit associated with shock wave lithotripsy is that itis a rather simple procedure. But it has been found that there is arelatively high rate of kidney stone recurrence following shock wavelithotripsy.

Transurethral lithotripsy or ureteroscopy represents one suchalternative form of treatment. This treatment involves the use of smallfiber optic instrument (endoscope) called an ureteroscope which allowsaccess to the calculus in the ureter or kidney. The ureteroscope can bea rigid ureteroscope or more commonly, a flexible ureteroscope. Theureteroscope allows the medical professional to visualize the stone asthe ureteroscope moves along the ureter or enters the kidney by way ofthe bladder and the urethra. Once the calculus is visualized, abasket-like device is used to grasp smaller stones and remove them. Ifthe calculus is excessively large to remove as a single piece, it can bebroken into a smaller pieces by using laser energy.

The third form of treatment is percutaneous nephrolithotomy. Thisprocedure is often used with relatively larger calculus that cannot beeffectively treated with either ESWL or URS. Percutaneousnephrolithotomy involves nephrostomy; making an incision at theappropriate location, needling by paracentesis needle, positioning aguide wire through the paracentesis needle's lumen into the kidney underradiographic guidance, and then expanding perforated site. A nephroscopeis then moved into the kidney via nephrostomy to visualize the calculus.Fragmentation of the calculus can be performed using an ultrasonic probeor laser.

Though these procedures have been commonly used, they are susceptible ofcertain short comings. For example, the ESWL procedure results in arelative large number of small calculi or small stones, while otherprocedures require a relatively narrow and long access route or aredifficult to implement due to the inability to accurately capture thestones. In addition to, many crush pieces should be removed one by onein URS and PCNL procedure. The procedure time can also be excessivelylong, and can result in a relatively low “stone free rate.” Therecurrence rate can also be unacceptably high. And the potential patientcomplications (e.g., ischemia of the ureter, obstruction of ureter,back-flow and/or high-stress to the renal pelvis, infection of theurinary tract, and other possible injury) can be undesirably high.

SUMMARY

One aspect of the disclosure here involves a method comprising removingfrom a lumen in an ureteral access sheath a calculus retrieving deviceused to retrieve calculus in a living body, wherein the living bodyincludes a ureter extending between a bladder in the living body and akidney in the living body, at least a portion of the ureteral accesssheath being located in the ureter, and wherein the calculus retrievingdevice is removed from the lumen of the ureteral access sheath while theureteral access sheath is positioned in the living body, with calculusbeing located in the lumen in the ureteral access sheath followingremoval of the calculus retrieving device from the ureteral accesssheath. The method also involves introducing a raking member into thelumen in the ureteral access sheath, moving the raking member along thelumen in the ureteral access sheath in a forward direction toward thekidney so that the raking member approaches and moves beyond thecalculus to position the raking member between the kidney and thecalculus, outwardly expanding the raking member when the raking memberis positioned between the kidney and the calculus, moving the expandedraking member along the lumen in the ureteral access sheath in arearward direction toward the proximal end of the ureteral access sheathso that the expanded raking member captures the calculus and moves thecaptured calculus toward the proximal end of the ureteral access sheath,and removing the raking member as well as the calculus from the lumen ofthe ureteral access sheath.

In accordance with another aspect, a method involves introducing araking part into a lumen in an ureteral access sheath in which islocated calculus, wherein the raking part is introduced into theureteral access sheath while at least a part of the ureteral accesssheath is located in an ureter in a living body, and wherein the rakingpart is expandable in outer size from a first state in which the outersize of the raking part is relatively smaller to a second state in whichthe outer size of the raking part is relatively larger. The method alsoincludes moving the raking part along the lumen in the ureteral accesssheath in a forward direction toward the calculus in the lumen of theureteral access sheath while the raking part is in the first state,continuing to move the raking part along the lumen in the ureteralaccess sheath in the forward direction to position the raking part inthe first state beyond the calculus, expanding the raking part from thefirst state to the second state when the raking part is positionedbeyond the calculus, moving the raking part in second state along thelumen in the ureteral access sheath in a rearward direction that isopposite the forward direction so that the raking part in the secondstate rakes away the calculus in the lumen of the ureteral accesssheath, and removing the raking part as well as the calculus from thelumen of the ureteral access sheath.

Another aspect of the disclosure here involves a method comprisingintroducing a raking part into a lumen in an ureteral access sheath inwhich is located calculus, wherein the raking part is introduced intothe ureteral access sheath while at least a part of the ureteral accesssheath is located in a living body, moving the raking part in a firstdirection along the lumen in the ureteral access sheath toward thecalculus in the lumen of the ureteral access sheath, continuing to movethe raking part in the first direction along the lumen in the ureteralaccess sheath to position the raking part beyond the calculus, and atleast partially occluding the lumen in the ureteral access sheath by wayof the raking part. After the lumen in the ureteral access sheath is atleast partially occluded by the raking part, the raking part is movedalong the lumen in the ureteral access sheath in a direction oppositethe first direction so that the raking part rakes out the calculus.

Other features and aspects of the methods disclosed here will becomemore apparent from the following detailed description considered withreference to the accompanying drawing figures in which like elements aredesignated by like reference numerals.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic illustration of a system useful to retrievecalculus/calculi, including a retrieving device connected to anoperation member (not shown in FIG. 1) through the intermediary of alumen in an elongated body.

FIG. 2 is a side view, partially in cross section, of a retrievingdevice according to an embodiment representing an example of theretrieving device disclosed here.

FIG. 3 is a front view of the impeller forming a part of the retrievingdevice shown in FIG. 2.

FIG. 4 is a schematic illustration of a portion of the human anatomy,including the urinary tract.

FIG. 5 is a schematic illustration of a human kidney, illustrating therenal pelvis, a lower calix (lower renal calix), a middle orintermediate calix (middle or intermediate renal calix), and an uppercalix (upper renal calix).

FIG. 6 is a schematic illustration of the retrieving system, includingthe retrieving device connected to the operation member through theintermediary of an elongated body such as an endoscope (ureteroscope).

FIG. 7 is a schematic illustration of a portion of human anatomyincluding the kidney connected to the bladder by the ureter.

FIG. 8 is a schematic illustration of an ureteral access sheathillustrating calculus in the ureteral access sheath followingoperational procedures implemented to retrieve and move or removecalculus from a living body.

FIG. 9 is a schematic side view of the ureteral access sheath in whichare located calculus and an endoscope.

FIG. 10A is a perspective view of a raking member with a raking part ina closed or collapsed state, and FIG. 10B is a perspective view of theraking member with the raking part in an open or expanded state.

FIG. 11 is a schematic illustration of the raking member positioned inan ureteral access sheath and movable between two positions.

FIG. 12A is a perspective view of an example of structural aspects ofthe raking part and FIG. 12B is an enlarged view of a portion of theraking part depicted in FIG. 12A.

FIG. 13 is a perspective view of the raking member positioned in theureteral access sheath illustrating operation aspects of the rakingmember.

FIG. 14 is a perspective view of the raking member.

FIG. 15A is a cross-sectional side view of a portion of the rakingmember with the raking part in the closed or contracted state accordingto another embodiment, and FIG. 15B is a cross-sectional side view ofthe raking member with the raking part in the open or expanded state.

FIG. 16 is a perspective view of the raking member positioned in anureteral access sheath and illustrating operation aspects of the rakingmember.

FIG. 17 is a perspective view of another embodiment of the rakingmember.

FIGS. 18A-18D are perspective views of another embodiment of the rakingmember positioned in an ureteral access sheath.

FIG. 19A is a perspective view of gathering member with a gathering partin the closed or contracted state, and FIG. 19B is a perspective view ofthe gathering member with the gathering part in the open or expandedstate.

FIG. 20 is a perspective view of the gathering member positioned in theureteral access sheath and illustrating operation aspects of thegathering member.

FIG. 21 is a perspective view of the gathering member.

FIG. 22 is a side view of the gathering member provided with a lumen foran irrigation tube.

FIG. 23 is an enlarged view of the portion of the gathering member inFIG. 22 circled by a dotted outline.

FIG. 24 is a schematic illustration of the gathering member positionedin an ureteral access sheath and movable between two positions.

FIG. 25 is a perspective view of the gathering member positioned in theureteral access sheath illustrating operation aspects of the gatheringmember.

FIG. 26 is a perspective view of the gathering member with the gatheringpart in the open or expanded state.

FIG. 27 is a perspective view of the gathering member with the gatheringpart in the closed or contracted state.

FIG. 28 is a perspective view of a suction member used to retrieve andremove calculus.

FIG. 29 is a perspective view of the suction member positioned in theureteral.

DETAILED DESCRIPTION

Set forth below is a detailed description of features and aspects of theretrieving system, device and operational procedure or method describedhere as examples of the disclosed invention. The systems, devices andoperational procedures disclosed here for retrieving calculus haveuseful application to retrieve calculus/calculi located in the livingbody, including calculus/calculi located in the kidneys (kidney stones).The references below to calculus should be understood to refer tocalculus in the singular as well as calculi in the plural. It is also tobe understood that the methods, systems and devices disclosed here arenot limited to retrieving calculus in a living body. Calculus as usedhere naturally includes stones (calculus) of various sizes, inclusive ofcalculus fragments generated by the lithotripsy.

Generally speaking, the calculus retrieving device disclosed here, asrepresented by the several embodiments representing examples of theinventive retrieving device (and method), is configured to be positionedinside a living body at a position which will allow the retrievingdevice to suck-in or draw-in calculus to be retrieved. Set forth belowis a detailed description of features and aspects of the calculusretrieving system, including a calculus retrieving device, and methoddescribed here by way of various embodiments representing examples ofthe disclosed inventions. The systems, devices and methods oroperational procedures disclosed here for retrieving calculus haveparticular useful application to retrieve calculus located at places inthe human body where removal of the calculus may otherwise be difficultdue to, for example, the need to traverse a rather sharp curve to accessthe target site and/or the need to enter a rather narrow region to movetoward and reach the target site.

Generally speaking, the calculus retrieving device disclosed here, ascharacterized by the several embodiments representing examples of theinventive calculus retrieving device (and method), is configured to bepositioned inside a living body, at a position adjacent the location ofcalculus to be retrieved from the living body. The calculus(stone/stones) is drawn towards the retrieving device by creating asuction force in the retrieving device. After the calculus is retrieved,the calculus is retained or held by the retrieving device. Theretrieving device can then be moved to the new location in the livingbody at which the retrieved calculus is to be repositioned. The retainedcalculus is subsequently released at the new location in the livingbody. Appropriate procedures (e.g., lithotripsy) can then be performedwith respect to the calculus which has been moved. Alternatively, theretained calculus can be subsequently removed from the living body.

Turning now to the drawing figures, FIG. 1 illustrates, in a schematicfashion, a system 20 for retrieving and moving (removing) calculus(stone or stones) located in a living body. The system 20 includes aretrieving device 30 and an elongated body 40 possessing a lumen todeliver the retrieving device 30 to the desired place in the livingbody. In this illustrated embodiment representing one example of thesystem disclosed here, the elongated body 40 is an endoscope,particularly an ureteroscope. The endoscope or ureteroscope 40 includesa lumen or instrument channel 42, which receives a portion of theretrieving device 30, as will be described in more detail below. Duringuse of the retrieving device 30, the endoscope 40 is introduced into theliving body by way of a ureteral access sheath 24. That is, the ureteralaccess sheath 24 is located in a lumen in the living body, and theendoscope 40 is introduced into and passes through a lumen 28 in theureteral access sheath 24.

Additional details and features associated with the calculus retrievingdevice 30 can be seen with reference to FIGS. 1, 2 and 3. The calculusretrieving device 30 includes a suction head 50 comprised of anelongated body or housing 51 having an open distal end 52. The housing51 is a tubular housing possessing a lumen 55 defining an interior ofthe housing 51. The housing 51 can be configured as a cylindricalelongated body or housing.

The retrieving device 30 also includes a rotatable suction-producingpart located inside the housing 51. In the illustrated embodiment, therotatable suction-producing part is in the form of an impeller 60. Asshown in FIGS. 1 and 2, the impeller is positioned in the housing 51 ata location spaced away from (i.e., proximally or rearwardly) the opendistal end 52. An example of the impeller 60 is illustrated in FIG. 3.The impeller 60 includes a plurality of circumferentially spaced apartfins or blades 62 that are fixed to a central hub 64. The fins or blades62 of the impeller 60 may be twisted fins or blades. The hub 64 is fixedor connected to a rotatably driven shaft 72 forming part of the deviceso that the shaft 72 and the impeller 60 rotate together as a unit. Theimpeller 60 is configured so that rotation of the impeller 60 in onerotational direction produces suction in the lumen 55 (in the interior)of the housing 51, while rotation of the impeller 60 in the oppositerotational direction produces the opposite result, namely an outwardlydirected force out of the lumen 55. The blades 62 of the impeller 60shown in FIGS. 2 and 3 are preferably twisted from the distal tip of theblades 62 (radially outermost tip of the blades) toward the bottomportion of the impeller where the blades are mounted. When the directionof the impeller rotation is the same as the twist direction of theblades 62, a suction force is generated. This direction of rotation ofthe impeller is referred to as overspin direction.

The drive shaft 72 that is connected to the hub 64 of the impeller 60 ispositioned inside a shaft cover 70 and is covered by the shaft cover 70which forms part of the device. In the illustrated embodiment, the driveshaft 72 is completely covered by the shaft cover 70. The shaft cover 70is fixed to the housing 51 forming the suction head 50 so that movementof the shaft cover 70 results in movement of the suction head 50(including the housing 51 and the impeller 60).

The housing 51 forming the suction head 50 includes a plurality ofcircumferentially spaced apart openings or through holes 54. Theseopenings or through holes 54 are positioned closer to the proximal endof the housing 51 than the distal end of the housing 51. These openingsor through holes 54 form outlets (an exhaust path) during operation ofthe retrieving device, as will become more apparent from the descriptionbelow. That is, liquid (e.g., water) which has been drawn into thehousing 51 of the suction head 50 during operation of the retrievingdevice 30 is exhausted or discharged out of the suction head 50 by wayof the outlets 54.

The suction head 50 further includes a filter 56 located inside thehousing 51 at a position between the distal end of the impeller 60 andthe open distal end 52 of the suction head 50. This filter 56 is adisc-shaped mesh member that allows the passage of fluid (e.g., liquidsuch as water), while also preventing the passage of calculus which hasbeen retrieved through operation of the retrieving device 30. The filter56 possesses an outer periphery (outer circumferential surface) incontact with the inner periphery of the suction head 50. The filter 56is positionally fixed within the interior of the housing 51 forming thesuction head 50.

The suction head 50 also includes a retrieval space 58 located betweenthe filter 56 and the open distal end 52 of the housing 51. As will bedescribed in more detail below, this retrieval space 58 is configured toreceive calculus which has been retrieved as a result of the operationof the retrieving device 30.

During operation of the retrieving device 30, the suction head 50 islocated at a position in a living body (a lumen in a living body) toretrieve calculus. That is, the suction head 50 is positioned relativeto the calculus to be retrieved such that during operation of theretrieving device 30, the calculus will be drawn towards (suckedtowards) the suction head 50. When the suction head 50 is properlypositioned relative to the calculus to be retrieved, the impeller 60 isrotatably driven through operation of a drive device connected to thedrive shaft 72. The drive device rotates the drive shaft 72, which inturn rotates the impeller 60. The impeller 60 is rotatably driven in adirection to create suction in the interior of the housing 51 that drawscalculus toward the open distal end 52 of the suction head 50. Thesuction force created by the rotation of the impeller 60 drawsrelatively smaller calculus (schematically shown in FIG. 1 andidentified as 68) through the open distal end 52 of the suction head andinto the retrieval space 58 in the housing 51. The suction force createdby the rotation of the impeller 60 can also draws relatively largercalculus into contact with the distal end of the suction head 50. Thatis, calculus possessing an outer dimension larger than the size of theopen distal end 52 of the suction head 50 can nevertheless be drawntowards the suction head 50 and retained by the suction head 50 bycreating sufficient suction force in the interior of the housing 51 thatholds the relatively larger calculus in contact with the distal end ofthe suction head 50.

Thus, by positioning the suction head 50 in the living body so that theopen distal end 52 of the suction head 50 is located at a position thatwill allow the calculus (i.e., calculus to be retrieved) to bedrawn-into or sucked into the retrieval space 58 upon rotationaloperation of the impeller 60, it is possible to retrieve calculus andhold the retrieved calculus either in the retrieval space 58 or at thedistal end of the suction head 50. As the impeller 60 is rotated to drawcalculus toward the suction head 50, liquid (e.g., water) is drawn intothe retrieval space 58 by way of the distal open end 52 of the suctionhead 50. This liquid is passes through the filter 56, and is exhaustedor discharged outside the housing 51 of the suction head 50 through theopenings or through holes 54. On the other hand, the filter 56 is sizedto ensure that calculus which is drawn into the retrieval space 58 ofthe suction head 50, does not pass through the filter 56. The rotationaloperation of the impeller 60 thus causes liquid flow in which liquidenters the distal open end 52 of the suction head 50, passes through thefilter 56, and exits through the through holes or openings 54 in thesuction head 50. Depending upon operation of the impeller 60, the liquidexhausted through the openings or through holes 54 can also be at leastpartially drawn back into the interior of the suction head 50, thuscreating a rather turbulent and continuous liquid cycle in which thesame liquid is repeatedly drawn into the suction head, exhausted throughthe suction head 50, drawn into the suction head, etc. This turbulentand continuous liquid cycle can help facilitate retrieval of calculus inthe retrieval space 58 of the suction head 50. This is because thesuction force per rotation of the impeller is increased. In addition,the calculus tends to float, making it easier to draw-in or retrieve thecalculus. When drawing-in calculus in a narrow lumen in a living body(e.g. ureter), the continuous liquid cycle helps prevent fluidsurrounding calculus from drying up.

Set forth next is a description of ways in which the system forretrieving calculus disclosed here can be used, as well as a descriptionof operational procedures performed using the calculus retrievingsystem. Calculus that is not excessively large can be retrieved andremoved from the living body using the retrieving system, device andoperational procedures or methods disclosed here. But it is sometimesnecessary or desirable to break-up calculus located in a living body.For instance, if the calculus is relatively large (e.g., larger than theureter diameter), it is not possible to remove the calculus from theliving body. In such situations, it would be desirable to break-up thecalculus into smaller size pieces. This can oftentimes be accomplishedusing lithotripsy. Circumstances may make it difficult to performlithotripsy to break-up calculus in the living body. For example, thecalculus may be located at a place where damaged tissue exists, forexample in a portion of the ureter in which there is damaged tissue.Alternatively, the calculus may be located in a portion of the livingbody (e.g., ureter) that is rather small in size (i.e., a narrow space)and difficult to access with appropriate instrumentation and equipmentfor performing lithotripsy (e.g., a lower calix). The retrieving systemand retrieving device disclosed here can be used to retrieve calculus,move the retrieved calculus to a new (different) location which presentsa larger space (e.g., the kidney or an upper calix) to performlithotripsy or which presents a region where there is normal(non-damaged tissue) tissue.

As explained, the retrieving device and system disclosed here can beused to retrieve calculus from a living body and remove the retrievedcalculus from the living body. The calculus which is to be retrieved bythe retrieving system disclosed here can be calculus located at anyplace that is accessible by the retrieving system disclosed here.Referring to FIG. 5, examples include calculus located in the ureter108, calculus located in the renal pelvis 101, calculus located in oneof the calices 102, 104, 106, etc. The retrieving device and systemdisclosed here can also be used to retrieve calculus from one place inthe living body, move the retrieved calculus to a new (different) placein the living body where, for example, lithotripsy can be more easilyperformed to break-up the calculus, and then release the retrieved andmoved calculus at the new location. By way of example, and withreference to FIG. 4, it is possible to retrieve calculus at the locationX in the ureter (representing an example of a region of narrow size ordamaged tissue) and move the retrieved calculus to the position X′ inthe ureter (representing an example of a region of larger size or normalnon-damaged tissue). It is also possible to retrieve calculus at thelocation Y (representing an example of a region of narrow size ordamaged tissue) and move the retrieved calculus to the position Y′ inthe kidney (representing another example of a region of larger size ornormal non-damaged tissue).

To retrieve and remove/move the calculus, a retrieving system such asthe retrieving system 20 shown in FIG. 6 can be used. Specifically, thecalculus retrieving device 30 is used, together with the operatingmember 26 and the endoscope 40 (ureteroscope). The operating member 26is connected to the shaft cover 70, so that operation of the operatingmember 26 causes the shaft cover 70 to move. That is, the operation ofthe operating member 26 causes the shaft cover 70 to axially move, whichin turn causes the suction head 50 (including the impeller 60 and thefilter 56) to also axially move. FIG. 6 schematically illustrates thatthe shaft 72 positioned within and extending along the axial length ofthe shaft cover 70 is connected to a driving device 28 (e.g., a gearedmotor). Operation of the driving device 28 rotates the shaft 72, whichin turn rotates the impeller 60 positioned in the housing 51 of thesuction head 50 of the calculus retrieving device 30. As shown in FIG.6, the shaft cover 70 and the shaft 72 extend from the operating member26, enter an inlet 44 of the instrument channel 42 in the ureteroscope40, pass through the ureteroscope 40, and exit at an outlet at thedistal end portion 46 of the ureteroscope 40.

In use, the shaft cover 70 is connected to the housing 51 of the suctionhead 50, and the proximal end of the shaft cover 70 and the shaft 72 areinserted into the outlet of the instrument channel 42 at the distal endportion 46 of the ureteroscope 40. The shaft cover 70 and the shaft 72are pushed through the lumen (instrument channel 42) in the ureteroscope40 until the proximal end of the shaft cover 70 and the proximal end ofthe shaft 72 exit out of the inlet 44 of the ureteroscope. The proximalend of the shaft 72 is then connected to the driving device 28, whilethe proximal end of the shaft cover 70 is fixed to the operating member26.

In the case of the endoscope 40 being an ureteroscope, the ureteroscopeis preferably a flexible ureteroscope. The ureteroscope 40 includes aviewing system that includes an objective lens or camera 48schematically illustrated in FIG. 1 (and FIG. 16). In a known manner,this provides a field of view for the user or operator to facilitatecarrying out the procedure involving locating calculus, retrieving thecalculus, moving the calculus to the new location and releasing thecalculus at the new location.

The description above explains that the retrieval of calculus using theretrieving system 30 disclosed here by way of example involvesintroducing the ureteral access sheath 24 into the lumen in the livingbody to position the ureteral access sheath 24 at the desired locationin the lumen in the living body while the proximal end of the ureteralaccess sheath 24 remains outside the living body, introducing theretrieval system 30 into the instrument channel 42 in the endoscope 40(i.e., inserting the proximal end of the drive shaft 72/shaft cover 70into the outlet end of the instrument channel at the distal end of theendoscope 40 (ureteroscope) and advancing the drive shaft 72/shaft cover70 along the instrument channel 42 toward the proximal end of theinstrument channel until the drive shaft 72/shaft cover 70 are locatedoutside of, and proximally beyond the proximal end of, the instrumentchannel 42), introducing the endoscope 40 (with the suction head 50 andthe drive shaft 72/shaft cover 70) into the ureteral access sheath 24that is positioned in the lumen of the living body (the endoscope 40 isintroduced into the proximal end of the ureteral access sheath 24, whichproximal end of the ureteral access sheath 24 is positioned outside theliving body), advancing the endoscope 40 (with the suction head 50 andthe drive shaft 72/shaft cover 70) along the ureteral access sheath 24and to the location in the lumen in the living body at which is locatedthe calculus to be retrieved. When the calculus is retrieved, theretrieval system is moved into the ureteral access sheath 24, and theretrieval system 30 is either removed from the living body or is movedto another location in the living body.

The operational procedure described above is utilized at least in partbecause the suction head 50 forming a part of the retrieval device 30may be too large to introduce into and move along the instrument channel42 of the endoscope 40.

It is possible that calculus (calculus fragments) may become depositedin the interior of the ureteral access sheath 24, and the presence ofcalculus in the ureteral access sheath 24 can present problems. Forexample, as the endoscope 40 is moved back and forth within the ureteralaccess sheath 24, calculus in the ureteral access sheath 24 can damagethe endoscope 40.

As described above in the description of the retrieval device 30illustrated in FIGS. 1, 2 and 6, the suction head 50 is utilized to drawcalculus into the interior of the housing of the suction head 50. Thesuction head 50 is moved along the ureteral access sheath 24 to thedesired location for retrieving calculus. After the calculus is drawninto the housing of the suction head 50, the suction head 50 is pulledrearwardly or drawn back into the ureteral access sheath 24 andultimately removed from the living body or moved to another location inthe living body by moving the ureteroscope in which the suction head ismounted. As the suction head 50 moves or is pulled in the rearwarddirection along the ureteral access sheath 24, calculus that have beenretrieved in the housing of the suction head may tend to fall out of thehousing of the suction head and become deposited on the inner surface 28of the ureteral access sheath 24 as illustrated in FIG. 8. In addition,calculus (especially small sized calculus such as fragments of calculusgenerated by lithotripsy) tend to flow into the ureteral access sheathas shown in FIG. 8 by virtue of fluid flow. This fluid flow can beurinary flow and can also result from taking the endoscope in and out ofthe ureteral access sheath 24.

Calculus in the interior (lumen) of the ureteral access sheath 24 candamage the endoscope as the endoscope moves back and forth within theureteral access sheath 24. An example of this potential damage isillustrated in FIG. 9 which shows the endoscope 40 movable back andforth within the ureteral access sheath 24, as indicated by the arrow,and during this back and forth movement the endoscope 24 is in contactwith the calculus 168 in the lumen of the ureteral access sheath 24. Inaddition, the lithotripsy procedure results in a relative large numberof small fragments of calculus, and these small-sized fragments have theability (sufficient size) to damage the endoscope 40. Such calculusfragments can be deposited rather easily in the interior of the ureteralaccess sheath 24, but are difficult to remove from the interior of theureteral access sheath 24 by the retrieving procedure in existence.

Set forth below is a description of various ways in which calculus canbe removed from the ureteral access sheath 24 to reduce the likelihoodof damage to the endoscope 40.

Before turning to the details of the various embodiments for removingcalculus from the ureteral access sheath 24, reference is made to FIG. 7which schematically illustrates the ureter 108 connecting the bladder110 to the kidney 100. FIG. 7 also schematically illustrates theureteral access sheath 24 positioned in a lumen in the living body. Asillustrated by way of example, the access sheath 24 passes through thebladder 110, and at least the distal portion of the ureteral accesssheath 24 is located in the ureter 108. It is of course to be understoodthat that the ureteral access sheath 24 may be positioned closer to orin the kidney 100, or spaced farther from the kidney 100, than thatillustrated in FIG. 7. The illustration in FIG. 7 is simply intended toshow a location for the ureteral access sheath 24 during the usagedescribed above.

One method or operational procedure for removing calculus from theinterior (lumen) of the ureteral access sheath 24 is illustrated inFIGS. 10A, 10B, 11, 12A, 12B, 13 and 14. One embodiment of the method oroperational procedure utilizes a raking member 120 illustrated in FIGS.10A and 10B. The raking member 120 includes an elongated shaft 24possessing a distal end connected to an expandable and collapsibleraking part 122. FIG. 10A illustrates the raking member 120 in a firststate or collapsed state in which the raking part 122 is closed orcollapsed, whereas FIG. 10B illustrates the raking member 120 in asecond state or expanded state in which the raking part 122 is open orexpanded. In the open or expanded condition of the raking member 120,the raking part 122 is enlarged relative to the raking part 122 when theraking member 120 is in the closed or collapsed state shown in FIG. 10A.

One possible operational procedure involving the raking member 120 is asfollows. The raking member 120 in the closed state shown in FIG. 10A ispositioned in the instrument channel of the endoscope 40 (ureteroscope).The endoscope 40 together with the raking member 120 is then advanced inthe forward direction to introduce the endoscope 40 together with theraking member 120 into the ureteral access sheath 24. The endoscope 40together with the raking member 120 is then moved along the lumen in theureteral access sheath 24 to approach the calculus in the ureteralaccess sheath 24 to be removed. The forward movement of the endoscope 40is stopped in advance of the calculus. Another procedure involvesintroducing the endoscope 40 (ureteroscope) into the ureteral accesssheath 24 while the ureteral access sheath 24 is positioned in the lumenof the living body, and introducing the raking member 120 (in the closedstate) into the instrument channel 42 of the endoscope 40 while theendoscope 40 is in the ureteral access sheath 24. The raking member 120in the closed state is then advanced along the instrument channel 42 sothat the raking member 120 in the closed state enters the ureteralaccess sheath 24. The forward movement of the endoscope 40 is stopped inadvance of the calculus.

The raking member 120 is then moved along the instrument channel 42 ofthe endoscope 40 and is introduced into the ureteral access sheath 24.The raking member 120 continues to be moved in the forward direction(toward the kidney) within the lumen of the ureteral access sheath 24 sothat the raking member 120 approaches the calculus 168 in the lumen ofthe ureteral access sheath 24. Throughout this axial forward movement,the raking member 120 is kept in the closed state shown in FIG. 10A. Theaxial forward movement of the raking member 120 in the ureteral accesssheath 24 continues until the raking member 120 in the closed statemoves past, or is located beyond, the calculus 168 in the ureteralaccess sheath 24. After the raking member 120 in the closed state passesthe calculus 168 in the ureteral access sheath 24 (i.e., the calculus168 are positioned between the raking member 120 and the bladder 110(FIG. 7)), the raking part 122 of the raking member 120 is moved to theopened or expanded position so that the raking member 120 is in the openor expanded state generally illustrated in FIG. 11. The raking part 122is expanded after the raking part 122 is positioned on the far side ofthe calculus 168 (i.e., so that the calculus 168 are positioned betweenthe bladder and the expanded raking part 122). This is identified asposition P1 in FIG. 11.

The expansion of the raking part 122 to the open or expanded state asshown in FIG. 11 at least partially occludes the lumen in the ureteralaccess sheath 24. In the illustrated embodiment, the expanded rakingpart 122 contacts at least a part of the inner surface of the ureteralaccess sheath 24 to form a seal with the inner surface of the ureteralaccess sheath 24. The raking part 122 can be configured to fully occludethe lumen in the ureteral access sheath 24. This can be accomplished byconfiguring the raking part 12 so that when the raking part 122 is openor expanded, most part of the entire outer periphery of theexpanded/open raking part contacts the inner surface of the ureteralaccess sheath 24.

The raking member 120 with the raking part 122 in the open or expandedcondition shown at P1 in FIG. 11 is pulled in the rearward direction(i.e., towards the bladder 110) as generally indicated by the arrow inFIG. 11. This can be accomplished by pulling or otherwise operating theshaft 124. That is, the user or operator can pull on the elongated shaft24, or the elongated shaft can otherwise be manipulated, to move theenlarged raking part 122 toward the calculus. As the expanded rakingpart 122 moves in the rearward direction, the expanded raking part 122rakes the calculus 168. The calculus 168 are thus moved in the rearwarddirection together with the rearward movement of the expanded rakingpart 122 as generally illustrated at position P2 in FIG. 11. Theexpanded raking part 122 continues to be pulled in the rearwarddirection until the raking member 120 is removed from the ureteralaccess sheath 24. The rearward or removal movement of the raking membercan be accomplished in a variety of ways. For example, the endoscope 40together with the raking member 120 can be moved rearwardlysimultaneously. Alternatively, the endoscope 40 and the raking member120 can be moved rearwardly in temporal difference (e.g., at first theraking member 120 is pulled back to some extent, then the endoscope 40is pulled back to some extent, then the raking member 120 is pulled backonce again, etc.) In a situation where the length of an elongated shaft124 is much greater than the length of the instrument channel 42 of theendoscope 40, the operator can remove the endoscope 40 from the ureteralaccess sheath 24 fully before the rearward and/or removal movement ofthe raking member 120. As the raking member 120 is removed from theureteral access sheath 24, so too is the raked-out calculus because theproximal end of the ureteral access sheath 24 is positioned outside theliving body.

FIG. 13 illustrates another aspect associated with this embodiment. Thelumen in the ureteral access sheath 24 contains liquid (e.g., water,normal saline solution, urine, etc.). Before inserting the ureteralaccess sheath 24, the urinary tract (i.e. the urethra, the bladder, theureter, and the kidney) are normally filled with a fluid. This fluid isurine and/or perfusion fluid of the endoscope 40 (e.g., water, normalsaline solution). Thus, when the ureteral access sheath 24 is insertedinto the urinary tract, fluid flows into (fills) the lumen of theureteral access sheath 24 naturally. The raking member 120 is configuredto create a disturbed flow of this liquid while the expanded raking part122 is pulled in the rearward direction (i.e., in the direction of thearrow in FIG. 11 to remove the calculus 168. The raking part 122 isconfigured so that in the expanded or open state illustrated in FIG. 13,the expanded raking part 122 includes a curved, somewhat trumpet-shapedsurface 126 that generates a disturbed flow as generally indicated bythe arrows in FIG. 13. The disturbed flow produced by the curved surfaceof the expanded raking part 122 together with the axial rearwardmovement of the expanded raking part 122 produces the turbulent flow ofliquid, and the turbulent flow of liquid tends to lift the calculus fromthe surface of the ureteral access sheath 24 and also prevents thecalculus from settling on the surface of the expanded raking part 22.The disturbed flow is thus beneficial in helping to remove calculuspresent in the lumen of the ureteral access sheath 24.

FIGS. 12A and 12B depict in a somewhat general fashion one possibleconfiguration of the expandable raking part 122. This embodimentillustrates one example of a frame structure forming part of theexpandable raking part 122. A cover is provided over this framestructure to result in the raking part 122 illustrated in FIGS. 10A,10B, 11 and 13.

Generally speaking, the frame structure forming a part of the expandableraking part 122 includes a plurality of arms each having one endpivotally connected to a common collar 138 fixed in place to a centralsupport 132. A plurality of links 134 are also provided, and one end ofeach link 134 is connected to a respective arm 130 and the opposite endof each link 134 is connected to a common tubular mount 136. Asschematically illustrated in FIG. 12A, the tubular mount 136 isconnected to connecting bar 137 to effect adjustment of the tubularmount 136 along the central support 132. The structure shown in FIGS.12A and 12B is similar to the frame structure of an umbrella. By virtueof this construction, the tubular mount 136 can slide along the centralsupport 132 so that the arms 130 pivot or rotate between a collapsedposition where the arms 130 are generally parallel to the centralsupport 132 (i.e., the closed condition or state of the raking member120 shown in FIG. 10A) and an outwardly expanded position where the arms130 project outwardly such as shown in FIGS. 12A and 12B (i.e., the openor expanded condition or state of the raking member 120 shown in FIG.10B).

FIG. 14 illustrates one example of an overall configuration of theraking member 120. The raking member 120 includes a handle 135 connectedto the elongated shaft 124. The raking member 120 also includes anadjustment element 139 that, in this illustrated embodiment, is mountedon the handle 135. The adjustment element 139 can be a manually operableadjustment element in the form of a slide that is manually slidable bythe user or operator to open/expand the raking part 122 andclose/collapse the raking part 122. The adjustment element 139 isconnected to the connecting bar 137 which in turn is connected to thetubular mount 136. Thus, the user can shift the raking part 122 betweenthe closed position shown in FIG. 10A and the open position illustratedin FIGS. 10B and 14 by operating the adjustment element 139 (i.e., bymanually sliding the slide). Moving the adjustment element 139 towardthe raking part 122 causes the raking part 122 to expand to the positionshown in FIGS. 10B and 14, and moving the adjustment element 139 awayfrom the raking part 122 causes the raking part 122 to close or collapse(fold) as illustrated in FIG. 10A.

During use of the raking member 120, the user or operator can hold thehandle 135 of the raking member 120 and, when the raking part 122 is inthe closed position shown in FIG. 10A, introduce the closed raking part122 into the instrument channel 42 of the endoscope 40 (ureteroscope).Using the handle 135, the raking member 120 is advanced along theinstrument channel 42 of the endoscope 40 so that the raking part 122 isultimately positioned outside the instrument channel beyond the distalend of the endoscope 40. As described above, after the raking part 122in the closed position is introduced into the ureteral access sheath 24,the closed raking part 122 is advanced in the direction toward thecalculus in the ureteral access sheath 24. The closed raking part 122 isultimately positioned just beyond the calculus 168 in the ureteralaccess sheath 24 that are to be removed as indicated by position P1 inFIG. 11. The user or operator can then operate the adjustment element139 (e.g., by sliding the slide in a forward direction toward the rakingpart 122) to cause the raking part 122 to shift from the closed stateshown in FIG. 10A to the open state illustrated in FIGS. 10B and 14.While still gripping the handle 135, the user or operator can beginpulling the open/expanded raking member 120 in the rearward directiontoward the calculus 168 in the ureteral access sheath 24. The rearwardlymoving expanded raking part 122 captures and pulls along the calculus168 in the ureteral access sheath 24. The rearward movement of theexpanded raking member 120 is similar to that discussed above.

FIGS. 15A, 15B and 16 illustrate another embodiment of the raking member220. In this embodiment, the raking part 222 is provided with severalliquid discharge ports 221 as seen in FIG. 15B and FIG. 16. These liquiddischarge ports 221 are connected to the interior of the raking part222. The interior of the raking part 222 is also in fluid communicationwith a lumen 225 passing through the elongated shaft 224. This lumen 225is connected to (in fluid communication with) a source of liquid 226schematically illustrated in FIG. 15B. The liquid source 226 suppliesliquid to the lumen 225 which in turn supplies the liquid to theinterior of the raking port 222 and the liquid discharge ports 221. Thesource of liquid can be a liquid-containing syringe.

The operational procedure involving use of the raking member 220 shownin FIGS. 15A and 15B is as follows. First, the raking member 220 isintroduced into the instrument channel of the endoscope 40(ureteroscope) as described above and is moved to a position just beyondthe calculus 168 in the ureteral access sheath 24 that are to be removedin the manner described above. The raking member 220 is moved to aposition just beyond the calculus 168 in the ureteral access sheath 24while the raking part 222 is in the closed position illustrated in FIG.15A. Next, the raking part 222 is shifted to the open condition in whichthe raking part 222 is expanded as illustrated in FIGS. 15B and 16. Thiscan be accomplished in the following way.

Each of the liquid discharge ports 221 consists of or includes a checkvalve (generally identified as 223 in FIG. 15A). In the first step(changing from closed condition shown in FIG. 15A to the open conditionshown in FIG. 15B), the check valves 223 of the liquid discharge ports221 are closed and so the fluid flowing in the lumen 225 can inflate theraking part 222. In the second step (achieving the situation shown inFIG. 16), the check valves 223 of the liquid discharge ports 221 arepartially open and so the fluid in the lumen 225 can be exhausted fromthe inflated raking part 222 and can retain the open (i.e. inflated)condition of the raking part 222.

The expanded raking part 222 is then moved toward the calculus 168 inthe ureteral access sheath 24. Liquid is also discharged from thedischarge ports 221. According to a preferred operational procedure, theraking member 220 is pulled in the rearward direction towards thecalculus 168 while at the same time liquid is discharged from thedischarge ports 221. FIG. 16 illustrates the liquid discharged from thedischarge ports 221 while the expanded raking part 222 is raking thecalculus 168.

The liquid discharged from the discharge ports 221 helps lift thecalculus off the interior surface of the ureteral access sheath 24 sothat it is easier to rake-out the calculus fragments. In thisembodiment, the calculus 168 in the ureteral access sheath 24 aresubjected to being raked-out by the raking part 222 and also beingwashed-out by virtue of the liquid introduced into the ureteral accesssheath 24 by way of the discharge ports 221 in the raking part 222.

FIGS. 17 and 18A-18D illustrate two additional embodiments of the rakingmember. The embodiment of the raking member 320 illustrated in FIG. 17is similar to the embodiment illustrated in FIGS. 10A and 10B, exceptthat the raking member 320 also includes a plurality of raking brushes330. These raking brushes 330 are fixed to the elongated shaft 324 andproject outwardly away from the elongated shaft 324. These rakingbrushes provide an additional mechanism for raking-out or removingcalculus in the ureteral access sheath when the expanded raking part 322is moved in the rearward direction.

The raking member 420 illustrated in FIGS. 18A-18D is also similar tothe embodiment of the raking member described above and illustrated inFIGS. 10A and 10B, except that the embodiment of the raking member 420in FIGS. 18A-18D includes a plurality of expandable raking parts 422,422′, 422″ rather than a single raking part. As shown in FIG. 18A, theexpandable raking parts 422, 422′, 422″ are axially spaced apart fromone another along the elongated shaft 424.

In the embodiment illustrated by way of example in FIG. 18A, thedistal-most raking part 422 possesses the largest outer size orcircumference (outer diameter) when in the expanded state, and then thesize or outer dimension of the raking parts in the expanded state becomeprogressively smaller moving away from the distal-most end as shown inFIG. 18A. This decreasing size configuration creates separated retrievalspaces 458 between axially adjacent pairs of the expanded raking parts422, 422′, 422″. This decreasing size of the successive expanded rakingparts 422, 422′, 422″ helps prevent the calculus from settling on thesurface of the expanded raking parts. This is depicted in FIGS. 18B-18Dwhich show that the calculus are divided automatically into theseparated retrieval spaces 458. If the collected calculus becomes alarge mass that is collected at one place (a single retrieval space),the pulling force required to pull the retrieved calculus may becomeexcessively large. And if the calculus being retrieved includesrelatively larger calculus, the most proximal part of the raking membercontacts the calculus first. The illustrated configuration of the rakingmember 420 is thus able to sort the calculus according to size.

In addition, interspaces 459 exist between the outer periphery of theexpanded raking parts 422, 422′, 422″ and the inner surface of theureteral access sheath 24. The dimension of the interspace progressivelyincreases from the expanded raking part 422 possessing the larger sizecircumference to the expanded raking part 422″ possessing the smallersize circumference.

It is also to be understood that the embodiments of the raking members320, 420 shown in FIGS. 17 and 18A-18D can be utilized with featuresassociated with other disclosed embodiments of the raking member. Forexample, the raking parts 322, 422 of the raking members 320, 420 shownin FIGS. 17 and 18A-18D can be provided with liquid discharge ports suchas illustrated in FIGS. 15A, 15B and 16.

The embodiments described above and illustrated in FIGS. 10A-18D involvea raking member that rakes-out calculus in the lumen of the ureteralaccess sheath. Set forth next is a description of several embodiments ofan alternative manner of removing calculus from the interior of theureteral access sheath. These alternative embodiments utilize agathering member.

FIGS. 19A, 19B and 20 illustrate one embodiment of a gathering member550. The gathering member 550 includes an openable and closablegathering part 552 connected to a manipulation wire 554. The gatheringmember 550 also includes a sheath 556. The manipulation wire 554 passesthrough the outer sheath 556.

FIG. 19A illustrates the gathering member 550 in a closed or collapsedstate in which the gathering part 552 is closed or collapsed and islocated in the sheath 556. FIG. 19B illustrates the gathering member 550in an open or expanded state in which the gathering part 552 is open orexpanded and is located outside the sheath 556. The gathering part 552is shiftable from the closed state in which the gathering part 552 islocated inside the sheath 556 to an opened state in which the gatheringpart 552 is outside the sheath 556 through manipulation or operation ofthe manipulation wire 554. Similarly, the gathering part 552 isshiftable from the opened state in which the gathering part 552 isoutside the sheath 556 to the closed state in which the gathering part552 is located inside the sheath 556 through manipulation or operationof the manipulation wire 554.

The gathering part 552 can be made of a shape-memory material (e.g.,NiTi wire). When made of this material, the gathering part 552 isnormally in the open state in the absence of an applied force or load,but is configured to be collapsed to the closed state and positionedinside the sheath 556 as illustrated in FIG. 19A in the presence of anapplied force or load (i.e., the force/load that arises when thegathering part 552 is pulled into the sheath 55 through operation of themanipulation wire 554). When the applied force/load is removed (i.e.,when the gathering part 552 is moved to a position outside the sheath556), the gathering part 552 automatically returns to the open orexpanded state shown in FIG. 19B.

An example of an operational procedure or method involving the use ofthe gathering member shown in FIGS. 19A, 19B and 20 is as follows.Initially, the gathering part 552 is in the closed state located insidethe sheath 556 as illustrated in FIG. 19A. The gathering member 550 inthe state shown in FIG. 19A is introduced into the instrument channel 42in the endoscope 40 (ureteroscope) which is located in the ureteralaccess sheath 24 positioned in the lumen in the living body (e.g., theureter). The gathering member 550 is advanced along the instrumentchannel 42 and is ultimately introduced into the ureteral access sheath24. The gathering member 550 in the closed state shown in FIG. 19A isadvanced along the ureteral access sheath 24 in a direction towards thecalculus to be removed (i.e., the calculus in the ureteral access sheath24 that are to be removed). The movement of the gathering member 550 isstopped when the distal end of the gathering member 550 is positionedadjacent to but in front of the calculus to be removed (i.e., thegathering member 550 is positioned between the calculus and thebladder). At this time, the gathering member 550 is positioned relativeto the fragments of calculus 168 as indicated at position P1 in FIG. 24.

The gathering member 550 is then moved in the forward direction towardsthe calculus 168 (i.e., from position P1 toward the position P2 in FIG.24). This movement of the gathering part 552 causes the calculus 168 inthe ureteral access sheath 24 to move into the open gathering part 552.After the calculus 168 are located in the gathering part 552, thegathering member 550 is pulled rearward toward the bladder andultimately removed from the ureteral access sheath 24. If the calculusare relatively small, the gathering part 552 containing the calculus canbe stored (pulled back) into the sheath 556. If the calculus arerelatively small, the gathering member 550 whose the gathering part 552contains the calculus can be pulled back into the instrument channel 42of the endoscope 40. If the calculus are not relatively small, thegathering part 552 containing the gathered calculus and the endoscope 40can be simultaneously moved rearwardly. In this latter situation, beforepulling back the gathering part 552 containing the calculus, theoperator can retract/adjust the size of the inner cavity of thegathering part 552 by withdrawing the manipulation wire 554 to preventcalculus from dropping off (falling out). Sometimes, in the procedure ofreducing the size of the inner cavity of the gathering part 552, thewithdrawn wire of the gathering part 552 can be used to grasp/keep thecalculus effectively.

FIG. 19B illustrates that the gathering part 552 can be provided with ashake-up part 558. This shake-up part 558 is in the form of aprojection, or a projecting scoop, that projects distally away from thegathering part 552 over a limited circumferential extent of thegathering part 552. That is, the shake-up part 558 does not extendaround the entire circumferential extent of the gathering part 552. Asillustrated in FIG. 20, the shake-up part 558 acts as a projecting scoopthat can be used to help lift the calculus 168 from the surface of theureteral access sheath 24 and into the open gathering part 552.

FIGS. 21, 22 and 23 illustrate additional details associated with thegathering member. As illustrated in FIGS. 22 and 23, the gatheringmember 550 includes a guide part 560 provided with a groove or lumen 562extending along the length of the guide part 560. The lumen receives abase wire 553 of the gathering part 552 as shown in FIGS. 22 and 23, andallows the base wire 553 (the gathering part 552) to slide along thelumen 562 in the guide part 560. The lumen is configured to include anarrowed opening that prevents the base wire from falling out. Thus, theguide part 560 provides the guide for moving the gathering part betweenthe open and closed position and for guiding the gathering part 552 intothe sheath 556.

FIGS. 25-27 illustrates a variation on the direction of the gatheringmember 550 illustrated in FIGS. 21, 22 and 23. In this illustratedembodiment, the guide part 560 includes a lumen 570 which receives anirrigation tube 572. In the position shown in FIG. 25, the irrigationtube 572 passes through the lumen 570 and extends distally beyond thedistal end of the guide part 560. The irrigation tube 572 can beconfigured in the manner shown in FIG. 25 to include a curve or bend toappropriately direct irrigation liquid discharged from the dischargeport or nozzle 574. The irrigation tube 572 is connected to a suitablesource of liquid (e.g., water, saline, etc.) The source can be aliquid-filled syringe.

As illustrated in FIG. 25, the irrigation tube 572 is preferablyarranged so that the discharge nozzle or port 574 from which the liquidis discharged is angled. In this way, liquid discharged from the nozzleor port is directed at the wall of the ureteral access sheath 24. Theliquid discharged from the irrigation port 574 is directed at calculus168 on the inner surface of the ureteral access sheath 24, causing thecalculus 168 to be lifted off of the inner surface of the ureteralaccess sheath and captured in the open gathering part 552.

The irrigation tube 572 can be made from a shape-memory material. Theirrigation tube 572 can thus be accommodated in the lumen 570 of anelongated shaft 524, yet is bent such as in the manner illustrated inFIG. 25 when the distal portion of the irrigation tube 572 is positionedoutside the lumen 570. The irrigation tube 572 normally possesses thebent or curved configuration shown in FIG. 25 in the absence of anapplied force or load. When a force or load is applied to the irrigationtube 572 such as occurs when the bent or curved portion of theirrigation tube 572 is pulled into the lumen 570, shape or configurationof the irrigation tube 572 changes. When the distal portion of theirrigation tube 572 is outside the lumen 570 as illustrated in FIG. 25,the irrigation tube 572 returns to its normal configuration.

FIG. 25 also illustrates the distal end of the endoscope 40(ureteroscope). The viewing system defined by the object lens or camera48 at the distal end of the endoscope 40 can be used to visualize theliquid discharged from the discharge port 574 of the irrigation tube 572to be appropriately directed at the calculus 168 lying on the innersurface of the ureteral access sheath 24.

A further embodiment of the method or operational procedure for removingcalculus from the interior of the ureteral access sheath is illustratedin FIGS. 28 and 29. In this embodiment a retrieving device 30 similar tothe retrieving device 30 shown in FIG. 1 is employed. As discussed abovein detail, the retrieving device 30 includes a suction head that createssuction to draw calculus into the suction head 50. The calculus in theureteral access sheath 24 are removed by suction through operation ofthe suction head 50 as described above. FIG. 28 illustrates theretrieval device 30 positioned outside the ureteral access sheath. Thisis done simply for ease of illustration and understanding. In actualpractice, the retrieval device 30 is located in the ureteral accesssheath 24 as illustrated in FIG. 29.

The retrieving device 30 is preferably moved to a position within theureteral access sheath 24 that is on the bladder side of the calculus168. This can be accomplished in the same way described above withrespect to the raking members and the gathering members. When thesuction head 50 is positioned adjacent to, and on the bladder side of,the calculus 168 (i.e., the suction head 50 is preferably not moved pastthe calculus 168), the suction head 50 is operated so that the impellerin the housing of the suction head 50 rotates and creates suction thatdraws the calculus 168 located in the ureteral access sheath 24 into thesuction head housing. After the suction head 50 is operational (i.e.,after the impeller in the suction head housing is rotating and creatingsuction), the suction head is preferably moved forward toward thecalculus 168. The operation of the suction housing creates convection inthe ureteral access sheath 24 that helps lift the calculus from thesurface of the ureteral access sheath 24, thus facilitating drawing thecalculus 168 into the interior of the housing of the suction head 50.

Through operation of the suction head 50 in the manner described above,calculus 168 inside the ureteral access sheath 24 are drawn into theinterior of the housing of the suction head 50. After the calculus 168have been captured or retrieved and are held in the housing of thesuction head 50, the endoscope 40, together with the suction headholding the retrieved calculus fragments, can be pulled rearwardly toremove the endoscope and the suction head from the ureteral accesssheath 24, and ultimately removed from the living body. It is possibleto utilize the viewing system associated with the endoscope 40 (i.e.,the lens or camera 48) during operation of the suction head 50 tocapture or retrieve the calculus in the interior of the ureteral accesssheath 24. This endoscope viewing system can also be used in each of theembodiments of the raking member and gathering member described above.

The retrieval of the calculus and the retention of the calculus duringmovement of the suction head 50 can be accomplished by controllingvarious operational parameters of the suction head 50. These operationalparameters include the rotation operation of the impeller 60 (ON/OFF)and the rotation speed of the impeller 60. That is, by varying therotation operation and the rotation speed of the impeller 60, it ispossible to control the retrieval and the retention of the calculus.

During retrieval of the calculus, the impeller 60 is preferably rotated(i.e., the rotational operation is ON), is rotated at a relatively highspeed (e.g., 15,000 rpm-20,000 rpm), and is rotated in the overspindirection intended to create suction in the suction head 50. Thecalculus is thus drawn toward the open distal end 52 of the suction head50 and enter the retrieval space 58 as shown in FIGS. 28 and 29.

After the calculus has been retrieved, it is necessary to retain theretrieved calculus in the retrieval space 58 of the suction head 50while moving the suction head 50 to remove the retrieving device 30 fromthe ureteral access sheath 24. To retain the retrieved calculus, thedriving device 28 continues to operate (i.e., the rotational operationis ON) so that the impeller 60 continues rotating. The rotationdirection of the impeller 60 is the same as the rotation direction ofthe impeller during retrieval of the calculus. In addition, the rotationspeed of the impeller 60 can be the same relatively high speed as therotation speed of the impeller 60 during retrieval of thecalculus/calculi, or can be a slightly slower rotation speed (e.g.,12,000 rpm-15,000 rpm).

The retrieving device 30 has sufficient space in the retrieval space 58to retrieve the fragments of calculus. In addition, created suction flowcan pack the retrieved fragments of calculus closely in the retrievalspace 58. That is why, after the calculus has been retrieved from theureteral access sheath 24, the operator can choose whether to remove theretrieving device 30 from the ureteral access sheath 24 or to advancethe retrieving device 30 in the ureteral access sheath 24 toward thekidney for continuing the retrieving in a pathological area (i.e., theureter, the renal pelvis and/or the renal calix) in the living body. Toretain the retrieved calculus while moving the suction head 50 to movethe retrieving device 30 toward the kidney, the driving device 28continues to operate (i.e., the rotational operation is ON) so that theimpeller 60 continues rotating. The rotation direction of the impeller60 is the same as the rotation direction of the impeller duringretrieval of the calculus. In addition, the rotation speed of theimpeller 60 can be the same relatively high speed as the rotation speedof the impeller 60 during retrieval of the calculus/calculi, or can be aslightly slower rotation speed (e.g., 12,000 rpm-15,000 rpm).

The description above describes ways of positioning the raking member,gathering member and suction member at the desired place in the lumen inthe living body to remove the calculus. For example, it is possible tointroduce the raking member, gathering member and/or suction member intothe instrument channel 42 in the endoscope 40 while the endoscope isoutside the living body, introducing the endoscope 40 (the rakingmember, gathering member and/or suction member) into the ureteral accesssheath 24 that is positioned in the lumen of the living body (theendoscope 40 is introduced into the proximal end of the ureteral accesssheath 24, which proximal end of the ureteral access sheath 24 ispositioned outside the living body), advancing the endoscope 40 (withthe raking member, gathering member and/or suction member) along theureteral access sheath 24 and to the location in the lumen in the livingbody at which is located the calculus to be retrieved. Alternatively, itis possible, if the size of the raking member, gathering member and/orsuction member permits, to introduce the endoscope 40 into the ureteralaccess sheath 24 that is positioned in the lumen of the living body (theendoscope 40 is introduced into the proximal end of the ureteral accesssheath 24, which proximal end of the ureteral access sheath 24 ispositioned outside the living body), introducing the raking member,gathering member and/or suction member into the instrument channel 42 ofthe endoscope 40 while the endoscope 40 is in the ureteral access sheath24, advancing the raking member, gathering member and/or suction memberalong the instrument channel so that the raking member, gathering memberand/or suction member enters the ureteral access sheath 24 and isadvanced to the location in the lumen in the living body at which islocated the calculus to be retrieved.

Set forth above is a description of various embodiments of methods oroperational procedures, and devices, for removing calculus from theureteral access sheath 24. The raking and/or washing out procedures arequite advantageous because the efficacy of the removal operation is notsignificantly impacted by small-sized because the small-sized calculuscan be rather easily raked-out and/or washed-out. Similarly, thegathering embodiments are not negatively affected in a significant waywhen removing small-sized calculus because the efficacy of liftingcalculus via the shake-up part 558 and/or utilizing irrigation from thedischarge part or nozzle 574 are not influenced by small-sized calculusbecause the small-sized calculus can be fairly easily gathered and/orirrigated. Further, being able to adjust the reticulation of thegathering part 552 is useful to prevent small calculus from droppingoff, and the efficacy of suction is not influenced by the size of thecalculus because rather small-sized calculus are easy to be drawn in.

The detailed description above describes devices and methods forremoving calculus from a ureteral access sheath. The invention is notlimited, however, to the precise embodiments and variations described.Various changes, modifications and equivalents can be effected by oneskilled in the art without departing from the spirit and scope of theinvention as defined in the accompanying claims. It is expresslyintended that all such changes, modifications and equivalents which fallwithin the scope of the claims are embraced by the claims.

What is claimed is:
 1. A method comprising: removing from a lumen in anureteral access sheath a calculus retrieving device used to retrievecalculus in a living body, the living body including a ureter extendingbetween a bladder in the living body and a kidney in the living body, atleast a portion of the ureteral access sheath being located in theureter, the calculus retrieving device being removed from the lumen ofthe ureteral access sheath while the ureteral access sheath ispositioned in the living body, with calculus being located in the lumenin the ureteral access sheath following removal of the calculusretrieving device from the ureteral access sheath, the ureteral accesssheath possessing a proximal end; introducing a raking member into thelumen in the ureteral access sheath; moving the raking member along thelumen in the ureteral access sheath in a forward direction toward thekidney so that the raking member approaches and moves beyond thecalculus to position the raking member between the kidney and thecalculus; outwardly expanding the raking member when the raking memberis positioned between the kidney and the calculus; moving the expandedraking member along the lumen in the ureteral access sheath in arearward direction toward the proximal end of the ureteral access sheathso that the expanded raking member captures the calculus and moves thecaptured calculus toward the proximal end of the ureteral access sheath;and removing the raking member as well as the calculus from the lumen ofthe ureteral access sheath.
 2. The method according to claim 1, whereinthe raking member is introduced into the lumen in the ureteral accesssheath by first inserting the raking member into a channel in anureteroscope.
 3. The method according to claim 1, further comprisingoccluding the lumen in the ureteral access sheath while the rakingmember is positioned in the ureteral access sheath.
 4. The methodaccording to claim 1, wherein the raking member is outwardly expandedinto sealing contact with an inner surface of the ureteral accesssheath.
 5. The method according to claim 1, further comprisinggenerating a disturbed flow in the lumen of the ureteral access sheathwhile moving the expanded raking member along the lumen in the ureteralaccess sheath toward the proximal end of the ureteral access sheath, thedisturbed flow lifting at least some of the calculus from an innersurface of the ureteral access sheath.
 6. The method according to claim1, further comprising introducing a liquid into the ureteral accesssheath while moving the expanded raking member along the lumen in theureteral access sheath toward the proximal end of the ureteral accesssheath to wash away at least some of the calculus in the ureteral accesssheath.
 7. The method according to claim 6, wherein the liquid isintroduced into the ureteral access sheath while moving the expandedraking member along the lumen in the ureteral access sheath toward theproximal end of the ureteral access sheath by discharging liquid from atleast one discharge port of the raking member.
 8. The method accordingto claim 2, further comprising positioning the raking member in thelumen of the ureteral access sheath at a position beyond the calculus,and then moving the ureteroscope in a rearward direction.
 9. A methodcomprising: introducing a raking part into a lumen in an ureteral accesssheath in which is located calculus, the raking part being introducedinto the ureteral access sheath while at least a part of the ureteralaccess sheath is located in an ureter in a living body, the raking partbeing expandable in outer size from a first state in which the outersize of the raking part is relatively smaller to a second state in whichthe outer size of the raking part is relatively larger; moving theraking part along the lumen in the ureteral access sheath in a forwarddirection toward the calculus in the lumen of the ureteral access sheathwhile the raking part is in the first state; continuing to move theraking part along the lumen in the ureteral access sheath in the forwarddirection to position the raking part in the first state beyond thecalculus; expanding the raking part from the first state to the secondstate when the raking part is positioned beyond the calculus; moving theraking part in second state along the lumen in the ureteral accesssheath in a rearward direction that is opposite the forward direction sothat the raking part in the second state rakes away the calculus in thelumen of the ureteral access sheath; and removing the raking part aswell as the calculus from the lumen of the ureteral access sheath. 10.The method according to claim 9, wherein the raking part is introducedinto the lumen in the ureteral access sheath by first inserting theraking part into a channel in an ureteroscope.
 11. The method accordingto claim 9, further comprising occluding the lumen in the ureteralaccess sheath while the raking part is positioned in the ureteral accesssheath.
 12. The method according to claim 9, wherein the expansion ofthe raking part from the first state to the second state includesoutwardly expanding the raking part into sealing contact with an innersurface of the ureteral access sheath to occlude the lumen in theureteral access sheath.
 13. The method according to claim 9, furthercomprising generating a disturbed flow in the lumen of the ureteralaccess sheath while moving the expanded raking part in the rearwarddirection along the lumen in the ureteral access sheath, the disturbedflow lifting at least some of the calculus from an inner surface of theureteral access sheath.
 14. The method according to claim 9, furthercomprising introducing a liquid into the ureteral access sheath whilemoving the raking part in the rearward direction along the lumen in theureteral access sheath to wash away at least some of the calculus in theureteral access sheath.
 15. The method according to claim 14, whereinthe liquid is introduced into the ureteral access sheath while movingthe raking part in the rearward direction along the lumen in theureteral access sheath by discharging liquid from at least one dischargeport of the raking part.
 16. The method according to claim 9, whereinthe introduction of the raking part into the lumen in the ureteralaccess sheath comprises introducing a plurality of axially spaced apartraking parts into the lumen in the ureteral access sheath, each of theraking parts being expandable from a first state to a second state,moving the raking parts along the lumen in the ureteral access sheath inthe forward direction to position the raking parts beyond the calculus,expanding the raking parts from the first state to the second state, andmoving the expanded raking parts in the second state in the rearwarddirection to rake away the calculus in the lumen of the ureteral accesssheath.
 17. A method comprising: introducing a raking part into a lumenin an ureteral access sheath in which is located calculus, the rakingpart being introduced into the ureteral access sheath while at least apart of the ureteral access sheath is located in a living body; movingthe raking part in a first direction along the lumen in the ureteralaccess sheath toward the calculus in the lumen of the ureteral accesssheath; continuing to move the raking part in the first direction alongthe lumen in the ureteral access sheath to position the raking partbeyond the calculus; at least partially occluding the lumen in theureteral access sheath by way of the raking part; after at leastpartially occluding the lumen in the ureteral access sheath by way ofthe raking part, moving the raking part along the lumen in the ureteralaccess sheath in a direction opposite the first direction so that theraking part rakes out the calculus.
 18. The method according to claim17, further comprising releasing the at least partial occlusion of thelumen in the ureteral access sheath before removing the raking part fromthe lumen of the ureteral access sheath.
 19. The method according toclaim 17, wherein the at least partially occluding of the lumen in theureteral access sheath by way of the raking part includes enlarging anouter dimension of the raking part located in the lumen of the ureteralaccess sheath.
 20. The method according to claim 17, wherein the atleast partially occluding of the lumen in the ureteral access sheath byway of the raking part includes contacting an inner surface of the lumenin the ureteral access sheath with an outer surface of the raking partto fully occlude the lumen in the ureteral access sheath.